Autism is a lifelong developmental disorder which affects the way in which an individual communicates with, relates to and understands people and the world around them. The condition can affect people in different ways, and the severity of impairments can differ significantly between individuals. This has led to the term autism spectrum disorder (ASD) being used in diagnosis. Aspergers syndrome is a term often used to describe people with autism spectrum disorder who have normal or superior intelligence and who experienced no language delays in childhood. However, there is continuing debate about the validity of distinctions between Aspergers syndrome and, for example, high-functioning autism.
ASD's are characterized by a triad of impairments in the following areas:
- Impairments in social interaction, including difficulties relating, sharing and forming relationships with others.
- Impairment in social communication, including difficulties interpreting and expressing verbal and non-verbal communication.
- Impairments in imagination and social understanding, including difficulties with imaginative play, pretending, planning ahead and tendency toward detail focus at expense of global understanding
The way an individual presents with autism spectrum disorder will depend on many factors, including the severity of their experience of the autism triad, their intelligence (IQ) and personality. People with ASD can also experience other disorders or psychiatric illness which may further affect their abilities (only certain disorders or psychiatric illness are more likely to affect individuals with ASD).
Prevalence and CausesASD is estimated to affect ~ 1/110 individuals. Males are approximately 4 times more likely to be affected than females although this ratio may be even greater amongst individual with Aspergers Syndrome.
The exact causes of ASD are unknown, although it is recognized that environmental and, in particular, genetic factors are involved in causing the changes in brain function which produce symptoms of ASD.